Clean-in-Place Liquid Filling Systems For Modern Packaging Operations – Part 1

July 13, 2026

Executive Summary

Clean-in-Place (CIP) liquid filling systems are a core technology for manufacturers that need hygienic, repeatable, and efficient cleaning without frequent disassembly. In filling operations, CIP reduces downtime, improves consistency, and helps manage contamination risk across products such as bleach, food and beverage, personal care, household chemicals, and industrial liquids.

For companies operating high-throughput packaging lines, CIP is not just a sanitation feature; it is a production strategy. Properly designed CIP systems support faster changeovers, lower labor dependence, and better process control, especially when integrated into fillers, piping, tanks, and upstream/downstream packaging equipment.

What is CIP

CIP is the cleaning of process equipment in place, without major disassembly, by circulating cleaning, rinsing, and sanitizing solutions through the system under controlled conditions. In liquid filling environments, CIP is commonly applied to product tanks, filler fluid paths, nozzles, piping, and other enclosed contact surfaces.

Modern CIP systems usually follow a sequence such as pre-rinse, detergent wash, intermediate rinse, optional acid wash, sanitizing step, and final rinse. The objective is to remove residue and microorganisms while minimizing manual intervention and preserving line availability.

Why CIP Matters

The strongest business case for CIP is downtime reduction. Because the equipment remains assembled during cleaning, operators avoid time-consuming teardown and reassembly, which improves turnaround between batches and helps maintain output.

CIP also improves repeatability. Automated cleaning cycles standardize time, temperature, flow, and chemical concentration, reducing the chance of missed steps or inconsistent sanitation. That consistency is especially valuable in regulated or quality-sensitive sectors where contamination, flavor carryover, or chemical residue can create product loss and compliance risk.


Contact us for more information and review Parts 2 and 3 of this series. 

October 6, 2026
What Happens During Factory Acceptance Testing (FAT) Stages 5 - 7 Stage 5: Surface Finish, Coatings, and Safety Coatings and Finishes FAT also includes a review of protective coatings and surface finishes, important for both corrosion resistance and cleanability. Checks include: ● Confirming two coats of chlorinated rubber paint or equivalent on all iron surfaces where specified, especially for bleach and detergent applications. ● Ensuring no paint on any thread surfaces or leveling screws so adjustments remain possible. ● Verifying that brass wearing surfaces on sliders are not being scraped and are correctly aligned. These guidelines emphasize the importance of appropriate coatings and cleanable surfaces, particularly for food, beverage, and aggressive chemical products. Laub\Hunt’s attention to such details at FAT ensures long‑term durability and sanitation. Safety Devices and Nameplate As part of FAT, Laub\Hunt verifies: ● Presence and function of limit switches at the infeed star and on the infeed conveyor. ● Availability and accessibility of grease fittings and other routine‑maintenance points. ● Correct, legible nameplate data (model, serial, ratings), which customers will use for documentation and future parts orders. Best practices call for safety verification (guards, interlocks, e‑stops) and accurate identification plates as prerequisites for shipment. Laub\Hunt incorporates these checks to help customers meet safety and compliance requirements. Stage 6: Long‑Run Performance Trials Extended Run Test FAT is not limited to quick spot checks. Laub\Hunt performs extended run tests where the machine operates for a couple of hours at or near production speeds with water and bottles. During this period, technicians evaluate: ● What wears: observing cams, followers, sliders, and seals for abnormal heat, friction, or polish. ● What rubs or squeaks: diagnosing any contact or misalignment indicated by noise. ● Smooth transfer of bottles across bridge plates, transfer plates, donut plates, and conveyor chains, ensuring no stumbling or misfeeds. Longer‑duration FAT runs are essential for revealing latent issues that short trials miss—such as thermal growth, creeping misalignment, or intermittent jams. Laub\Hunt’s long‑run tests follow that logic and are documented as part of the FAT record. Torque Limiter and Overload Behavior Laub\Hunt’s checklist also calls for verifying the torque limiter: It must be adjustable so the machine can be pulled back while running and restarted from any position. During FAT, Laub\Hunt: ● Tests overload conditions to ensure the torque limiter slips or releases as designed. ● Confirms that the machine can resume operation without binding after an overload event. Tests of overload and emergency behavior ensures both equipment protection and operator safety. Including this in FAT means customers receive a machine whose protective systems have already been proven under controlled conditions. Stage 7: Special Tests for Detergent and Chemical Applications Suds and Chemical‑Behavior Tests For fillers intended for bleach, detergents, and other foaming or chemically aggressive products, Laub\Hunt performs specialized tests beyond standard water trials. These include: ● “Suds tests” using detergent or ammonia solutions to observe foam behavior in the bowl, valves, and overflow paths. ● Checks that level controls remain stable and that foam does not cause chronic false readings or spills. ● Validation that seals, coatings, and materials in contact with test solutions behave as designed. It is necessary to test performance under realistic process conditions, including foaming and temperature variations, before shipment. Laub\Hunt’s suds and chemical‑behavior tests are the result of decades’ experience in the bleach and household‑chemical markets. Stage 8: Spares, Accessories, and Documentation Counting Stars, Guides, and Spares A comprehensive FAT also ensures that everything promised in equipment order is present and accounted for. Laub\Hunt technicians: ● Count and record the number of stars and guides shipped. ● Verify the number of spare valves and confirm they are fully assembled and ready to use. ● Confirm that a grease gun and a tube of Parker O‑Lube (or equivalent) are packed with the filler. Best practices include checks that all auxiliary equipment, tools, and documentation are present, as these items are often critical to smooth commissioning. Final Documents and FAT Report Throughout the FAT, Laub\Hunt records: ● Test results, observations, and any deviations from expected performance. ● Adjustments made and final “zero settings” (e.g., fill volumes, speeds, and key alignment points). ● Outstanding minor items, if any, with a plan for resolution. Best practices call for a formal FAT report and acceptance certificate once criteria are met, with any minor punch‑list items documented separately. Laub\Hunt follows this model, ensuring that you have a shared, written record of what was tested and accepted before shipment. What FAT Means for You When Factory Acceptance Testing is complete, you receive a filler that has already: ● Been fully lubricated, aligned, and checked for mechanical integrity. ● Passed dry and wet functional checks, including leak tests, safety verifications, and extended runs. ● Demonstrated performance with your bottles under realistic conditions. ● Had its accessories, spares, and documentation verified and packed. Industry standards—and Laub\Hunt’s decades in liquid filling—show that this investment in the FAT dramatically reduces startup time, rework, and risk at your plant. By the time your machine reaches your dock, the heavy troubleshooting has already been done, allowing installation and commissioning to focus on integration and optimization rather than basic fixes. Contact us for more information. Also review stages 1-2 and stages 3-4.
September 30, 2026
What Happens During Factory Acceptance Testing (FAT) Stages 3 - 4 Stage 3: Dry Functional Testing Air and Control System Checks With the mechanicals validated and lubricated, Laub\Hunt conducts dry functional tests (i.e., no product yet) to confirm pneumatic and control behavior. This includes: ● Checking the air filter by running air through water to verify proper exhaust of air and any entrained moisture. ● Wiring and testing up‑and‑down solenoids, confirming the correct hoses and motions, and ensuring there are no wiring or plumbing errors. ● Setting pressure regulators for plungers and other actuators. ● Verifying float switch travel—typically at least 4 inches between on and off positions—and ensuring switches reliably trigger overflow pumps when specified. These steps represent best practices where PLC inputs/outputs, actuators, and interlocks are checked before any wet testing. Laub\Hunt’s checklist embeds these tasks in a structured, sign‑off format. Valve and Hardware Verification Still in the dry phase, technicians verify: ● Presence and condition of all valve components: blocks, washers, O‑rings, tips, and screws, with no missing parts and all fasteners snug. ● Adjustability of valves across the full outage range: clearing the bottle top, reaching the lowest fill level, and beyond. Other FAT protocols require similar checks to ensure valves and heads are complete and adjustable before any performance measurements are made. Laub\Hunt’s detailed valve checklist minimizes the risk of assembly omissions that could create leaks or inaccurate fills. Stage 4: Wet Test and Leak‑Tightness Water‑based Wet Test The core of FAT is the wet test, where the filler is run with water to verify leak‑tightness and system behavior under realistic hydraulic conditions. Laub\Hunt technicians: ● Check for leaks at valves, hose gaskets, manifolds, and piping to any vacuum pumps. ● Inspect rotating seals by deliberately stressing them side‑to‑side to see if leakage occurs. ● Verify that O‑rings at switches are lubricated and not leaking, and that Permatex or similar thread sealant is applied on specified switch threads. Laub\Hunt prioritizes leak tests, emphasizing the need to verify seals, connections, and wetted components before shipping. Laub\Hunt’s process ensures the entire liquid path is sealed and stable. Functional checks with water and bottles Simultaneously, the team verifies system functions under wet conditions: ● Confirming float switches control overflow pumps correctly. ● Running bottles through the filler to test stars and guides in real operation. ● Checking that valves reach and maintain target levels at different settings and that the full range of fill‑level adjustment is available. ● Ensuring the cam for “puffing” or venting seals properly on the upper tip O‑ring before being withdrawn from the valve. Water trials validate filling accuracy, container handling, and control logic before committing to performance metrics. Laub\Hunt integrates these into a single wet test phase, tightly linked to its checklist items. Contact us for more information. Also Review stages 1-2 and stages 5-7 .
What Happens During Factory Acceptance Testing (FAT) Stages 1-2
September 23, 2026
During Factory Acceptance Testing (FAT), Laub\Hunt Packaging Systems runs your filler through a structured, checklist‑driven trial in their plant—verifying lubrication, mechanical alignment